portable spa chemistry?

I recently aquired a used spa. The cabinet was trash but the shell was in perfect shape so now we are framing around the spa and plan on rebuilding the equipment platform today so we can liberate it from the trailer. It appeared to unstable to roll on pvc when whe got it home I was stopping every five minutes to pick up the last few peices of siding as made the trip home! As soon as we it stable we plan placing on our concrete patio and testing it. Spa chemistry anyone?

thanks
jennifer